<!doctype html> 
<html> 
<head> 
    <meta charset="utf-8"> 
    <title></title> 
</head>
<body>

<script type="text/javascript">
	onload = function(){

		//function a(){ alert(1)};
		function a(){
			alert(10);
		};

		setInterval(a,2000);
		
	}
</script>
</body>
<input type='button' value='d' id='ipt'>
</html>